U.S. patent number 6,937,748 [Application Number 09/659,772] was granted by the patent office on 2005-08-30 for left hand right hand invariant dynamic finger positioning guide.
This patent grant is currently assigned to Ultra-Scan Corporation. Invention is credited to Stephen M. Gojevic, Frank W. Keeney, Frederick W. Kiefer, John K. Schneider.
United States Patent |
6,937,748 |
Schneider , et al. |
August 30, 2005 |
**Please see images for:
( Certificate of Correction ) ** |
Left hand right hand invariant dynamic finger positioning guide
Abstract
An automatic finger guide for fingerprint scanners includes
active scan area on the scanner surface upon which one finger rests
and a non-active scan area on the scanner surface on which the
other finger(s) rest to provide stability, a stop post to indicate
how far forward to place the hand, a guide post to assist in
positioning the finger left to right or right to left as the case
may be, sensors on the post to provide feedback to the user to when
the hand is properly in place and to determine the position as to
where the finger comes to rest on the active scan area.
Inventors: |
Schneider; John K. (Snyder,
NY), Gojevic; Stephen M. (Tonawanda, NY), Keeney; Frank
W. (Williamsville, NY), Kiefer; Frederick W.
(Williamsville, NY) |
Assignee: |
Ultra-Scan Corporation
(Amherst, NY)
|
Family
ID: |
34864196 |
Appl.
No.: |
09/659,772 |
Filed: |
September 11, 2000 |
Current U.S.
Class: |
382/126 |
Current CPC
Class: |
G06K
9/00013 (20130101); G06K 9/00919 (20130101) |
Current International
Class: |
G06K
9/00 (20060101); G06K 009/00 () |
Field of
Search: |
;382/115,124,126 ;283/68
;356/71 ;235/380 ;340/5.8-5.86 ;704/246,273 ;902/4,25 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Ahmed; Samir
Attorney, Agent or Firm: Hodgson Russ LLP
Parent Case Text
CROSS REFERENCE TO A RELATED APPLICATION
Applicants hereby claim priority based on Provisional Application
No. 60/153,180 filed Sep. 10, 1999 and entitled "Left Hand Right
Hand Invariant Dynamic Finger Positioning Guide" which is
incorporated herein by reference.
Claims
What is claimed is:
1. An automatic finger positioning guide for fingerprint scanners
comprising: a) an active scan area on the scanner surface upon
which one finger rests and a non-active area on the scanner surface
on which one or more of the other fingers rest to provide
stability; b) a stop post on the scanner surface to indicate how
far to place the hand longitudinally thereof, the stop post being
located on the scanner surface in relation to the active scan area
so as to contact the vertex defined between the side of the one
finger and the side of an adjacent finger when the hand is properly
in place; c) a guide post on the scanner surface physically
separate from the stop post to assist in positioning the finger
laterally, the guide post being located on the scanner surface in
relation to the active scan area so as to contact a portion of the
side of the finger at a location between the stop post and the
finger tip when the hand is properly in place; and d) means to
indicate when the hand is properly in place.
2. The finger positioning guide according to claim 1, wherein
pressure sensitive membrane switches are provided on the stop post
and on the guide post.
3. The finger positioning guide according to claim 1, wherein
left-hand and right-hand guide posts and stop posts are provided on
the scanner surface.
4. The finger positioning guide according to claim 1, further
including a visual indicator on the scanner operatively connected
to the means to indicate when the hand is properly in place.
5. The finger positioning guide according to claim 1, wherein a
sensor is on at least one of the posts to indicate when the hand is
properly in place.
6. The finger positioning guide according to claim 1, wherein the
stop post and the guide post are so located relative to each other
on the scanner surface so that the guide post contacts the same
side of the one finger the vertex of which is contacted by the stop
post.
7. An automatic finger positioning guide for fingerprint scanners
comprising: a) an active scan area on the scanner surface upon
which one finger rests and a non-active area on the scanner surface
on which one or more of the other fingers rest to provide
stability; b) a stop post on the scanner surface to indicate how
far to place the hand longitudinally thereof, the stop post being
located on the scanner surface in relation to the active scan area
so as to contact the vertex defined between the side of the one
finger and the side of an adjacent finger when the hand is properly
in place; c) a guide post on the scanner surface to assist in
positioning the finger laterally, the guide post being located on
the scanner surface in relation to the active scan area so as to
contact a portion of the side of the finger at a location between
the stop post and the finger tip when the hand is properly in
place; d) means to indicate when the hand is properly in place; and
e) the stop post and the guide post being of electrically
conductive material so that a circuit is completed when the hand is
properly in place.
Description
BACKGROUND OF THE INVENTION
Inkless fingerprint scanners, also known as live scan fingerprint
readers or biometric devices, have been widely used for many years.
These systems obtain an image of the fingerprint without the use of
inks. Once an image is acquired, it is then processed and an
identification or verification of the individual's identity is
made.
Many different techniques have been used to obtain an image of the
finger including optical scanners, thermal scanners, capacitive
scanners, E-field sensors, ultrasonic scanners, and many more. Each
uses a different modality or technique to image the same physical
characteristic; the ridge structure of the finger. Each claim to
have certain advantages over the competing approaches.
The use of these systems is a two step process. The first step is
that the user must enroll into the system. The enrollment process
scans the individual's finger for the first time and stores it,
along with any other pertinent information needed for future use in
the identification or verification process. The second step is the
actual identification or verification process. In the case of
identification, the user's identity is now known and it is up to
the system to determine the identity. This process is usually
referred to as a cold search or a one-to-many. The verification
process is where the user presents their identity in the form of a
token such as a PIN code, ID Card, etc., and it is up to the system
to verify the identity using the fingerprint.
The majority of large-scale applications that have been attempted
with live scan fingerprint readers have been in an attended
application. That is, a trained attendant assists the user of the
live scan fingerprint reader by guiding the user in the proper
placement of the finger with respect to vertical and horizontal
position on the platen surface of the live scan fingerprint reader.
Proper placement of the finger is absolutely critical to obtain
maximum accuracy in the identification or verification process.
Usually, a display such as a computer monitor is used to show the
location of the finger on the platen, providing feedback to the
user and the attendant as to the position of the finger. In
addition to proper placement of the finger horizontally and
vertically, users often tend to roll the finger to one side or
another, thereby not imaging the main portion of the finger but
rather the side of the finger. Consequently, the attendant will
often assist in ensuring that the finger is flat on the fingerprint
platen and not rolled off to one side.
Using an attendant to assist the user and providing visual feedback
of the image severely limits the deployment of these systems. For
example, for most commercial applications the cost of a trained
fingerprint attendant to assist the user in the positioning of
their finger is prohibitive. Techniques to train the users on the
proper placement of the finger have been tried but generally do not
work. Even if they did, adding a PC Monitor near the fingerprint
scanner to provide positional feedback also raises the cost of the
system beyond what can be tolerated by most commercial
applications. Furthermore, the visual feedback system introduces
additional problems.
First, the user, by seeing the finger on the PC Monitor, will tend
to slide their finger into position until it is properly located.
Because of the friction between the skin and the platen, the
sliding effect introduces distortion of the fingerprint, thereby
introducing errors in the identification/verification process.
Second, many live-scan fingerprint readers cannot produce an image
of the finger fast enough to give the user the instantaneous
feedback they need to guide them. For these scanners, the use of a
display such as a PC Monitor is virtually useless.
In an attempt to solve this problem, some of these products have
tried a form of electrical or mechanical guide to assist the user
in the proper placement of the finger. Electrical guides are
normally some type of sensor or array of sensors that is detecting
the position of the finger on the platen surface and providing the
user feedback. Again, these devices would have the same problem
associated with them as does the PC Monitor. The user would slide
their finger to position it properly as instructed by the
positioning sensor, and this sliding would again cause distortion
of the fingerprint. Other electronic means have been proposed to
image a very large surface area, thereby ensuring that the entire
finger would be imaged. Then using image-processing techniques, the
tip of the finger would be located for processing the fingerprint
image. Unfortunately, for many fingerprint scanners, imaging a
large scan area would cause the image array such as a CCD to
increase in size, thereby increasing the cost of the system
significantly. For other fingerprint scanners, increasing the image
area would increase the scan time significantly thereby reducing
user acceptance and system throughout.
Stationary mechanical devices have been tried but have proven
ineffective. The variability in the length, width and height of
fingers makes it difficult to design a single guide to work for
everyone. In addition, many proposed techniques have proven
inappropriate due to the variability in the length of an
individual's fingernails.
These problems combined have restricted the deployment of live scan
fingerprint readers successfully into unattended applications.
SUMMARY OF THE INVENTION
An overall improvement can be made to all live scan fingerprint
readers by providing the automatic guide in accordance with the
present invention for properly positioning the finger horizontally,
vertically, and without rotation. Doing so will ensure that the
user's finger will be in the optimum position of the fingerprint
platen, without distortion, thereby enabling the highest possible
system accuracy. Furthermore, the system is able to do this without
the help of the user, an attendant, or a display such as a PC
Monitor. This makes the system user friendly and low cost, thereby
enabling the use of these devices in unattended applications.
The automatic finger guide of the present invention includes an
active scan area on the scanner surface upon which one finger rests
and a non-active scan area on the scanner surface on which the
other finger(s) rest to provide stability, a stop post to indicate
how far forward to place the hand, a guide post to assist in
positioning the finger left to right or right to left as the case
may be, sensors on the post to provide feedback to the user as to
when the hand is properly in place and means to determine the
position as to where the finger comes to rest on the active scan
area.
The following detailed description of the invention, when read in
conjunction with the accompanying drawings, is in such full, clear,
concise and exact terms as to enable any person skilled in the art
to which it pertains, or with which it is most nearly connected, to
make and use the invention.
BRIEF DESCRIPTION OF THE DRAWING FIGURES
FIGS. 1A and 1B are diagrammatic views illustrating the automatic
finger guide according to the present invention;
FIG. 2 is a top plan view, partly diagrammatic, of the finger guide
of the present invention for use with one type of scanner;
FIG. 3 is a side elevantional view, with parts removed, of the
apparatus of FIG. 2;
FIG. 4 is a perspective view of the finger guide of the present
invention for use with another type of scanner;
FIG. 5 is a diagrammatic view further illustrating an alternative
form of guide post of the finger guide of the present
invention;
FIGS. 6A-6C are diagrammatic views illustrating alternative finger
sensing arrangements for use in the finger guide of the present
invention; and
FIG. 7 is a perspective view of the finger guide of the present
invention used in another type of scanner
DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS
An overall improvement can be made to all live scan fingerprint
readers by providing the automatic guide as shown in FIGS. 1A and
1B for properly positioning the finger horizontally, vertically,
and without rotation. Doing so will ensure that the user's finger
will be in the optimum position of the fingerprint platen, without
distortion, thereby enabling the highest possible system accuracy.
Furthermore, the system is able to do this without the help of the
user, an attendant, or a display such as a PC Monitor. This makes
the system user friendly and low cost, thereby enabling the use of
these devices in unattended applications.
The fundamental approach for use in an unattended, verification
mode of operation is as follows:
First, increase the size of the surface of the fingerprint scanner
to allow two or more fingers to be placed down simultaneously. One
finger would rest on the active scan area (platen), the other(s)
would rest on an ordinary surface (non-active scan area) to provide
stability. This greatly minimizes the amount of rotation that can
be introduced since any rotation would tend to lift the hand off
the surface of the scanner.
Second, provide posts to assist the user in placement of the hand.
Two posts as a minimum would work. One to indicate how far forward
to place the hand (the stop post), and one to help position the
finger left to right (the guide-post). A mirror image of the posts
could be placed to allow left hand/right hand operation.
Third, place electronic sensors on the post to provide feedback to
the user as to when they have their hand properly in place. The
feedback could be visual such as LEDs, audible, or both.
Fourth, the position as to where the finger comes to rest on the
platen can then be determined. This can be done manually, or
automatically by the system through a variety of image processing
techniques.
The arrangement shown in FIGS. 1A and 1B is provided on the
operative surface of a fingerprint scanner, typically the top
surface 10 of the scanner. The scanner can be any of the types
previously mentioned hereinabove. With the above functionality
built into the system, the enrollment and verification process
would work in the following manner. In the enrollment process, the
user places their left or right hand 12 down onto the surface 10 of
the fingerprint scanner and ensures proper finger placement against
the guide post 14 or 16 and stop post 18 or 20 as indicated by
feedback sensors. The system scans a large portion of the finger on
the scanner platen 26 and determines the location of the tip of the
finger. The large portion of the finger must only be scanned during
the time of enrollment in order to ensure that the tip of the
finger is located and the complete fingerprint image is captured.
This increased scan time during the enrollment process is not
needed during the verification process and would therefore be
accepted by the users of the system. The system records the
fingerprint image or template, the location of the tip of the
finger, and any other pertinent information such as PIN code.
There are two fundamental approaches to implement the verification
process. The first approach is ideally suited for fingerprint
scanners that scan the finger mechanically, such as the ultrasonic
scanner 30 shown in FIGS. 2 and 3. By way of example, the scanner
of FIGS. 2 and 3 is similar to that shown and described in U.S.
Pat. No. 5,647,364 issued Jul. 15, 1997, the disclosure of which is
hereby incorporated by reference. The second approach is ideally
suited for scanners 40 that do not scan the finger mechanically as
shown in FIG. 4
The verification process for mechanical scanners is as follows. The
user enters their token ID such as the PIN code recorded at the
time of enrollment. The system retrieves the fingerprint
information that is to be compared, along with the location of the
tip of the finger. The system, using a stepper motor or other
motion controlling type of device, positions the scan head to the
proper position under the platen for that individual in order to
scan the finger. Since the scan head is in an optimum position,
only a normal size area of the finger needs to be scanned, thereby
minimizing the scan time. The user places their left or right hand
down onto the surface of the fingerprint scanner as they did during
enrollment and ensures proper finger placement against the guide
post and stop post as indicated by the feedback sensors. The finger
is scanned and the identity verification process takes place.
The verification process for non-mechanical scanners is as
follows.
For live scan fingerprint readers that do not scan the finger
mechanically, moving the solid state imaging array to directly
under the finger may or may not be feasible. In that case, rather
than moving the imaging array to position it under the finger, the
guide post and stop post could be moved and the image array kept
stationary. In this manner, the end result is the same in that the
tip of the finger rests directly over the imaging sensor.
In addition to the obvious advantages the finger guide has in an
unattended verification mode of operation, there are even
advantages when used in a non-verification mode or operations,
i.e., a cold search application. The accuracy and speed of
identifying an individual is directly related to finger placement
on the platen. In order to compare two images, the matching
algorithm must allow for translation and rotation. The tighter the
control on these two degrees of freedom, the faster a match can be
performed, with greater accuracy.
In this case, the enrollment process would store both the
fingerprint image and the location on the platen where the finger
was found. The second parameter, the location on the platen where
the finger was found, is directly related to the length of the
finger as measured from the length of the stop post to the tip of
the scanned image. Therefore, it can be used as a discriminator
into the large database of fingerprint images. Thus when an
individual is to be identified, they place their finger down onto
the platen. The system would not automatically search for the top
of the finger and begin scanning. Only the portion of the database
associated with that particular length of finger would have to be
searched, thereby not only improving accuracy (less images to
search), but also decreasing the overall search time.
There are some fingerprint scanners on the market that
simultaneously scan more than one finger. An approach similar to
that of the present invention could be used to assist in the
placement of the fingers on such scanners.
In the embodiment of FIGS. 1-4, the guide post and the stop post
both are of metal, and when the finger properly contacts both an
electrical circuit is completed to indicate that the finger is
properly positioned on the scanner. FIG. 5 shows an alternative
form of guide post provided with a pressure sensitive membrane type
switch 52 located along the surface of the guide post which is to
be contacted by the finger. The arrangement can be elongated and
comprising a pair of pads of conductive ink. Alternative approaches
such as impedance, resistive or capacitive switches and infrared
sensitive elements also can be employed.
FIGS. 6A-6C illustrate alternative finger sensing arrangements for
use in the finger guide of the present invention. Each of the
arrangements is in the form of a membrane switch construction and
would be located on a surface of the scanner in relation to the
active scan area. The arrangement of FIG. 6A includes a series of
individual keypad conductive ink buttons 60, 62, 64 and 66 along a
row or substantially linear path. FIG. 6B illustrates a single long
continuous strip 70 of conductive ink for sensing any part of the
finger. FIG. 6C shows an arrangement of many individual strips 74
(circuits) which functions to indicate whether or not the finger is
in place and to provide an indication of the finger length. The
strips are along a row or substantially linear path.
FIG. 7 shows the finger guide of the present invention in a
portable fingerprint scanner 80 adapted primarily for law
enforcement use. The finger guide post 82 is located on the top
surface 84 of the scanner in relation to the fingerprint scan area.
The scanner can be of the type shown in the above-referenced U.S.
Pat. No. 5,647,364 adapted for battery operation. The scanner can
be connected to a computer in the law enforcement vehicle either
via the hard wire connection or the RF communication link indicated
in FIG. 7. That is for the purpose of storing and processing the
fingerprint images down-loaded from the scanner. In operation, the
device is held by the law enforcement officer by means of the
handle 90, the subject places his finger on the scanner including
the scan area or platen 92 and when the finger is properly
positioned an indication is provided by the LED 94 as previously
described, whereupon the scanner is activated by the officer simply
by squeezing the trigger 96 and if a fingerprint image is obtained
this is indicated by another LED.
It is therefore apparent that the present invention accomplishes
its intended objectives. While embodiments of the present invention
have been described in detail, that is done for the purpose of
illustration, not limitation.
* * * * *